Line overflow recorder



May 3, 1938. R. E. coLLls Er Al.

LINE ovERFLow RECORDER Filed Jan. 29, 1957 SS w By O. MYERS 6?6. M

ATTORNEY Patented May 3, 1938 UNITED STATES Aram ortica LINE OVERFLOWRECORDER Application January 29, 1937, Serial No. 122,972

8 Claims.

applicable to the cross-bar system since they` either require an eXtraterminal for the line and a corresponding brush on the switch havingaccess thereto or depend on the connection with the busy line beingmaintained for an appreciable length of time. A typical example of thecross-bar system is disclosed in the patent cf W. W. Carpenter, No.2,689,921, granted Aug. 11i, 1937, in which it will be observed that thebusy or idle condition of the line is determined by the common controlequipment known as markers which recognize absence of ground on the linesleeve as the idle condition but do not immediately mark the lineengaged.

In accordance with the present invention, when it is desired to recordthe number of times that a line is called while busy, the arrangement cithe invention is inserted in the two leads yindividual to the line atthe line choice connector. Means is provided for holding the line idleto the marker irrespective of its actual condition together with meansresponsive to the test by the marker for recording the test andtransmitting a busy indication to the marker if the line is busy. Thisrecording means comprises. a pair of counting relays, only one of whichis operated if the line is idle and both of which are operated if theline is busy.

The invention will be more clearly understood from a consideration ofthe following description in connection with the drawing which showsparts of a terminating marker, line choice connector and line switchtogether with the line overflow register forming the basis of theinvention. In general the elements of the drawing have been selectedfrom the drawing of the Carpenter patent and the same referencecharacters have beenemployed. Reference is also made to that patent fora description of the complete operation of the system.

In general, the establishment of a connection with a called line isunder the control of a marker, which obtains access to the line by meansof .a line choice connector. The line choice connector is equipped witha number of twentyblock relays each closing points in two circuitsindividual to each of twenty lines. One of these is the sleeve or busytest circuit and the other'is a position indicating circuit. Thesecircuits terminate'in two cr'cssconnecting racks at the iirst of whichappear the sieeve leads of the lines and at the other of which appearterminals of the position relays. Cross-connections are made at theseracks to permit any desired arrangement of the lines cn the switchframes.

When it is desired to record the number of attempts` to reach a lineorprivate branch exchange group which fail because of a busy condition,the line overiiow register circuit is inserted in plac Vof these-twocross-connections.

Referring to the drawing, a portion of a marker is shown in rectangle131, a portion of a line choice connector is shown in rectangle liiEjtheline overflow register in rectangle 1133 and line 1269, primary lineswitch 1231i and hoid magnet 1201 in rectangle I E14.

When the marker has received the wanted line number it translates thedesignation into an indication of the choice, hundred-block andtwenty-block within which the line lies. 1t connects with the choice bymeans of connector 132, operating relay 321113. The hundred-block andtwenty-block indications cause the operation of twenty-block relay31118. With relays 31538 and 321i@ operated the twenty pairs of circuitscon trolled by relay 31123 are closed.

Assuming first a normal connection, the sleeve conductor 1229 of linelilil which appears at rack 3111 in terminal 3125 is connected asindicated by the arrow to terminal 3124 and to one of the left contactsof relay 31118. Likewise the corn responding right contact ci relay 31%which appears at rack 3135 in terminal 2122 is crossconnected asindicated by the arrow to terminal 3123 leading to the left winding ofrelay 313|.

Therefore, when relay 313e operates, it closes two circuits for eachline,` one from the sleeve of the line which will be grounded if theline is busy, for example, over conductor i229, crossconnectingterminals 31525 and 3124 at rack 31 1 1, left front contact of relay31153, armature 3213 of relay 323D, conductor 3215i, back contact ofrelay 11519, to the winding of test relay 5219 which is connected overconductor 5251 to battery. A similar circuit is closed for each of theother lines .in the twenty-block. A second circuit, individual to line1211@ may be traced from battery through the winding of relay 523,.leftcontact of relay 5243, which was operated over the normal contact ofrelay m and the other relays of that group, right back contact of relay4519, armature. 3226 of 'relay 3261i, kconductor 3221,

ller.

armature 3126 of relay 3100, cross-connecting terminals 3122 and 3123 atrack 3105, left'winding of relay 3101, armature 3222 of relay 3200 tothe winding of relay 5900 and battery.

Under these conditions-if the line is idle, none of the relays 5219,5239, or 5900 operate. Relay 3108 in operating connects ground overconductor 3130, armature 3205 of relay 3200, and conductor 326'1 to arelay arrangement shown for convenience as the timing arrangement 105resulting, after an interval suicient for the operation of relay 5219and other relays of the group, in the operation of relay 4534. Relay4534 closes a circuit through the units register 4810 to the armature ofthat relay of the group represented by relay 5219 which is connected tothe wanted line. Assuming that the circuit extends to relay 5219 andthat the relay is unoperated because the line is idle, this circuitextends over the back contact of relay 5219 to the winding of relay 4519and battery. Relay 4519 operates and locks over the back contact ofrelay 4530, opening the sleeve test circuit and connecting ground to thecircuit of relays 3101 and 5900 to start selection of a connectingchannel. The sleeve circuit is Connected to the winding of relay 4530 asa busy guard test during the selection of the channel.

If the line had been busy, relay 4519 would not be operated, but thecircuit controlled by relay 4534 would extend over the front contact `ofrelay 5219 to the busy back relay.

Assuming that it is desired to record the number of times that line 1200is tested while busy, the cross-connections indicated by arrows at racks3111 and 3105 are opened and the connections indicated by dotted linesare closed.

Whenever the line 1201 becomes busy, ground is connected to conductor1229 which with the recorder |03 in service, completes a circuit overterminals 3125 and 110, right back contact of relay 105, Winding ofrelay 111 and battery. Relay 111 locks over terminal 110 independent ofrelay 105 as long as the line remains busy.

When now relay 3100 operates in making a line test, the sleeve testcircuit is open at the contacts of relays and 10'1. Therefore, relay5219 cannot operate and after an interval relay 4519 operates. Relay4519 closes a circuit from ground over its right front Contact, armature3220 of relay 3200, conductor 3221, armature 3125 of relay 3108,contacts 3122 and 1018 at rack 3105, back contact of relay 101, innerleft back contact of relay 109, Winding of relay and battery.

Assuming rst that line 1200 is idle and relay 111 unoperated, theoperation of relay 106 closes a locking circuit through the windings ofrelays 106 and 109, outer left Contact of relay 106, armature 1 12 ofrelay 3200 to ground at the back contact of relay 4010. Relay 109 isheld shunted by the operating circuit of relay 105. Relay 106 opens theoperating circuit for relay 1 1 1 and connects terminals 3125 and 3124together by way of terminal 110, right front contact of relay 100 andterminal 1 13, thereby preparing the operating circuit of the holdmagnet 1201.

Relay 100 also completes a circuit, if the line is idle, from ground atthe back Contact of relay 111, back contact of relay 109, inner leftcontact of relay 105, terminals |14 and 3123, left Winding of relay3101, armature 3222 of relay 3200, Winding of relay 5900 and battery,substituting this circuit for the circuit normally closed by relay 4519.The call now progresses in the usual man- When the connection has beenestablished and tested for continuity, relay 4010 operates, opening thelocking circuit of relay 106 without permitting relay 109 to operatetherein.

If the line is busy and relay 1 1 1 is operated, the operation proceedsas for an idle line until relay 4519 operates. However, the circuit ofrelay 5900 is open at the contact of relay III so that no channelselecting operations can be started. As before, relay 106 operates overthe right front contact of 4519 and connects the sleeve of the linethrough to the left armature of relay 4519 so that the busy ground nowoperates relay 4530. Relay 4530 opens the locking circuit of relay 4519and that relay releases, transferring the grounded sleeve back to thetest relay 5219 which operates and in turn operates the busy-back relay.The release of relay 4519 opens the operating circuit of relay 100,permitting relay 109 to operate in the locking circuit. Relay 109further opens the operating circuits of relays 106 and 5900 and closes acircuit for relay 1 I5 which in turn operates meter 116 to record oneattempt to reach the line while busy.

The operation in the case of a group of private branch exchange trunksis the same, since the' last trunk of such a group is wired in the sameway as individual lines.

In the case of number checking on toll calls,

the line will, of course, be busy and, in order to prevent recording thenumber check as an attempted connection, relay 10'1 is provided. Thisrelay operates from relay 3102 in the line choice connector Which inturn is operated as soon as the connector is seized in connection with anumber checking call. Relay 10'1 in operating, immediately connectsterminals 3125 and 3124 together and terminals 3122 and 3123 together,by-passing the recorder. It also opens the operating circuit of relay100 to further prevent the functioning of the recorder.

What is claimed is:

1. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a conductor individual to said line,common control means including means for testing said line, and meansfor recording the number of times said line is tested while busy,comprising means inserted in said individual conductor responsive tosaid testing means when said line is idle to transmit a positionindication to said control means and responsive to said testing meanswhen said line is busy to record said test and transmit a busy signal tosaid control means.

2. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a conductor individual to said line,common control means including means for testing said line, and meansfor recording the number of times said line is tested while busy,comprising a pair of counting relays, inserted in said individualconductor, one of said relays responsive to said testing means when saidline is idle to transmit a position indication to said control means andboth of said relays responsive to said testing means when said'line isbusy to record said test and transmit a busy signal to said controlmeans.

3. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a test circuit individual to said line,a position indicating circuit also individual to said line, commoncontrol means including means for preparing said test circuit and saidposition indicating circuit, and means inserted in said test circuit andsaid position indicating circuit for recording the number of times saidline is tested while busy, comprising means for normally holding saidtest circuit open, means operated by said testing means over saidposition indicating circuit for completing said test circuit and eectiveto transmit a position indication to said control means if said line isidle.

4. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a test circuit individual to said line,a position indicating circuit also individual to said line, commoncontrol means including means for preparing said test circuit and saidposition indicating circuit, and means inserted in said test circuit andsaid position indicating circuit for recording the number of times saidline is tested while busy, comprising means for normally holding saidtest circuit open, means operated by said testing means over saidposition indicating circuit for completing said test circuit andeffective to transmit a position indication to said control means ifsaid line is idle, means operated under the control of a busy line forcanceling said position indication and means responsive to thecompletion of said test circuit to a busy line to operate a meter. Y

5. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a test circuit individual to said line,a position indicating circuit also individual to said line, commoncontrol means including means for preparing said test circuit and saidposition indicating circuit, and means inserted in said test circuit andsaid position indicating circuit for recording the number of times saidline is tested while busy, comprising a pair of counting relays, meansunder the control of one of said relays for normally holding said testcircuit open, means for operating said one relay over said positionindicating circuit and means controlled by said one relay eiective ifsaid line is idle to complete said test circuit and to transmit aposition indication to said control means and to prevent the operationof said second counting relay.

6. In a telephone system, a telephone line, means to mark said line busyby applying a busy condition to a test circuit individual to said line,a position indicating circuit also individual to said line, commoncontrol means including means for preparing said test circuit and saidposition indicating circuit, and means inserted in said test circuit andsaid position indicating circuit for recording the number of times saidline is teste-d while busy comprising a pair of counting relays, meansunder the control of one of said relays for normally holding said testcircuit open, means for operating said one relay over said positionindicating circuit, means controlled by said one relay effective if saidline is idle to complete said test circuit and totransmit a positionindication to said control means and to prevent the operation of saidsecond counting relay, means operated under the control of a busy linefor canceling said position indication, and means responsive to thecompletion of said test circuit to a busy line to cause the second ofsaid counting relays to operate a meter.

7. In a telephone system, a telephone line, switching means havingaccess to said line, common control means, means in said control meansformaking an initial busy test of said line, means responsive to saidinitial busy test for identifying the position.` of said line, meansresponsive to said position identification to select idle switchingmeans for connection with said line, means effective during said switchselection to maintain a busy guard test of said line, means forrecording the number of times a line is called when busy comprising ameter, Vmeans for marking said line idle to said initial busy test, andmeans responsive to said busy guard test if said line is busy to operatesaid meter.

8. In a telephone s'ystem, a telephone line, switching means havingaccess to said line, co-mmon control means, means in said control meansfor making an initial busy test of said line, means responsive to saidinitial busy test for identifying the position of said line, meansresponsive to said position identication to select idle switching meansfor connection with said line, means effective during said switchselection to maintain a busy guard test of said line, and means forrecording the number of times a line is called when busy comprising apair of counting relays, a meter, means under the control of one of saidrelays for marking said line idle to said initial busy test, and meansresponsive to said busy guard test if said line is. busy to cause theother of said counting relays to operate said meter.

RAYMOND E'. COLLIS. OSCAR MYERS.

